Animals are most likely to excrete a semisolid nitrogenous waste with:

Options

A. nephridia
B. malpighian tubules
C. kidneys
D. all of these

Explanation

To determine which organ is most likely used by animals to excrete a semisolid nitrogenous waste, we can analyze the options provided:

1. **Identify the types of nitrogenous waste**:
- Animals excrete nitrogenous waste in various forms, primarily as ammonia, urea, or uric acid. Uric acid is a semisolid waste product.

2. **Understand the classification of animals based on nitrogenous waste**:
- Animals that excrete uric acid are termed **uricotelic**. These animals typically conserve water and excrete nitrogenous waste in a less toxic, semisolid form.

3. **Examine the options**:
- **A. Nephridia**: Found in annelids (like earthworms), these structures excrete nitrogenous waste in a liquid form, primarily urea.
- **B. Malpighian tubules**: These are excretory structures found in insects and some arthropods. They excrete nitrogenous waste as uric acid, which is semisolid.
- **C. Kidneys**: Present in vertebrates (including humans), kidneys primarily excrete urea in a liquid form.
- **D. All of the other**: This option suggests that all the mentioned structures are involved in the excretion of semisolid nitrogenous waste, which is not accurate.

4. **Conclusion**:
- The correct answer is **B. Malpighian tubules**, as they are specifically adapted for the excretion of semisolid nitrogenous waste (uric acid) in uricotelic animals like insects.

### Final Answer:
**B. Malpighian tubules**